Insecticidal compounds and methods of combatting insects using phenyl-n-(1-alkenyl)-methylcarbamates

ABSTRACT

Phenyl-N-(1-alkenyl)-N-methylcarbamates and their use as insecticides.

United States Patent 11 1 1111 3,764,695 Chupp Oct. 9, 1973 INSECTICIDALCOMPOUNDS AND [56] References Cited METHODS OF COMBATTING INSECTS UNITEDSTATES PATENTS USING E i 'VUV'ALK 3,131,215 4/1964 Lemin 260/479METHYLCARBAMATES FOREIGN PATENTS OR APPLICATIONS [75] Invent: Mm PaulChuPP, Klrkwmd, 0152,501 10/1956 Germany 260/479 [73] Assignee: MonsantoCompany, St. Louis, Mo. J l b Primary Examinererome D. Go (1 erg [22]Filed: 1970 Assistant Examiner-Allen J. Robinson {211 A N 20,044Attorney-Paul C. Krizov, Neal E. Willis and John J.

Henschke, Jr. 1

[52] US. Cl 424/300, 260/468, 260/479 [57] ABSTRACT [51] Int. Cl A0ln9/20 [58] Field or Search 424/300 260/468 CPhenyl-N-(l-alkenyl)-N-methylcarbamates and their 260/479 use asinsecticides.

10 Claims, No Drawings 1 INSECTICIDAL COMPOUND AND METHOD or COMBATTINGINSECTS USING PHENYL-N-(l-ALKENYLJ- METHYLCARBAMATES wherein R is alkylor alkylamino of a maximum of six carbon atoms, R, R and R are hydrogenor alkyl of a maximum of four carbon atoms, R and R can together form analkylene group of three through six carbon atoms, and n is an integerfrom through 2.

The term alkenyl as used herein encompasses acyclic as well as cyclicalkenyl groups. When both R and R in the above formula are hydrogen oralkyl, the compounds are acyclic. When R and R are combined, however, toform an alkylene group, the alkylene group together with the ethylenelinkage combines to form a cycloalkenyl group having from five througheight carbon atoms.

In the above formula, the alkyl groups of R, R, R and R can be methyl,ethyl, n-propyl, secondary propyl, isopropyl, n-butyl, secondary butyl,tertiary butyl, isobutyl and the various forms of pentyl and hexyl, andR and R taken together can form the corresponding alkylene groups.

The N-acyclic alkenyl compounds of the present invention are readilyprepared by reacting a carbamoylchloride with a phenol or a phenoxide ofan alkali metal (e.g., sodium, potassium, or ammonium) in accordancewith the following general equation:

in which R, R, R R and n have the above identified significance. Thereaction is normally conducted in an ployed in the above reaction can beprepared by the following methods. When preparing the phenyl-N-acyclic-alkenyl-N-methylcarbamates of the invention, an aldehyde isreacted with methyl amine and the product thereof treated with phosgenein accordance with the following general equation:

The carbamoylchlorides utilized in preparing thephenyl-N-cyclo-alkenyl-N-methylcarbamates of this invention can beprepared by reacting an N-methyI-N- cycloalkylidine with phosgene asexemplified by the following reaction:

CHa

Alternately, the N-cycloalkenyl compounds of this invention are preparedby the reaction of a suitably substituted phenyl chloroformate with anN-methyl-N- cycloalkylidine.

The following examples will further illustrate the invention. In theseexamples, and throughout the specification, parts and percents are byweight unless otherwise indicated.

EXAMPLE 1 About grams of m-isopropylphenol and about 1,500 ml. ofdimethyl ether were charged into a suitable reaction vessel providedwith an agitator, thermometer, and reflux means. After the addition ofthe phenol was complete, about 182 grams of a 25 percent solution ofsodium methoxide was added dropwise with agitation. This resulted in theformation of the corresponding sodium phenoxide, and the methanol wasdistilled off. The reaction mixture was cooled to about roomtemperature, and about grams ofN-(2-ethyll-butenyl)N-methylcarbamoylchloride was added. The reactionmixture was then refluxed for about 2 hours and permitted to remain atroom temperature for about 72 hours. The salt was filtered off and thefiltrate taken up in methylene chloride, washed with an aqueous sodiumcarbonate solution, and then washed twice with water. The filtrate wasdried over magnesium sulfate which was subsequently removed byfiltration. The solvent was then stripped by evaporation, leaving aviscous oil which was identified as m-isopropylphenyl-N-(2-ethyl-1-butenyl)-N-methylcarbamate. This product 0 gave the followinganalysis: Calcd for: C l-l O N.

6 perature employed is not critical, and usually varies between roomtemperature and the boiling point of the particular solvent used. Thecarbamoylchloride em- Theory 74.14 percent C, 9.15 percent 11, 5.09percent N. Found 73.33 percent C, 9.02 percent H, 4.04 percent N.

EXAMPLE 2 About 12 grams of m-tolylchloroformate dissolved in about 100ml. of benzene were added to a reaction vessel as described in thepreceding example. Then about 8.5 grams of N-rnethyl-N-cyclohexylidenedissolved in about 50 mm. of benzene were added and the temperature ofthe reaction mixture maintained between about and C. The mixture wasstirred for a period of about 5 minutes and then about 7.8 grams oftriethylamine was added and the mixture heated at reflux for about 45minutes. The mixture was cooled, filtered, and the filtrate washed withwater, dried and the benzene removed under vacuum. The product thusobtained, m-tolyl-N-(cyclohexan-l-yl)-N- methylcarbamate, was analyzedfor C H O N, with the following results: Theory 77.4 percent C, 8.16percent H, 6.0 percent N. Found 75.52 percent C, 8.10 percent H, 5.48percent N.

Other compounds made in general accordance with the procedures of theabove examples include:

m-( l-methylbutyl) phenyl-N-( l-isobutenl -yl)-N- methylcarbamate m-(l-ethylpropyl) methylcarbamate m-(2-ethylpropyl)phenyl-N-(Z-ethyl-l-hexen-l-yl)- methylcarbamate m-( l-methylbutyl)yl)methylcarbamate m-isopropylphenyl-N-( 2-ethyl-l-buten-l-yl)-methylcarbamate phenyl-N-(Z-ethyl- 1 -butenl -yl)- phenyl-N-(l-isobutenl -yl)-N- phenyl-N-( 2-ethyll -hexen-l methylcarbamatern-isopropylphenyl-N-( isobutenl -yl )methylcarbamatem-methylaminophenyl-N-( l-isobutenl-yl)methylcarbamatem-ethylaminophenyl-N-( l-isobuten- 1 -yl)rnethylcarbamatem-hexylphenyl-N-( l-cyclooctenl -yl)-N- methylcarbamatem-ethylphenyl-N-( l-cyclohepten-l-yl)-N- methylcarbamate m-tolyl-N-(l-cyclopenten-l-yl)-N-methylcarbamatem-dimethylamino-N-ethenyl-N-methylcarbamate The terms insect andinsecticide are used herein in their broad common usage to includespiders, mites, ticks, and like pests which are not in the strictbiological sense classed as insects. Thus, the term insect is used torefer not only to those small invertebrate animals belonging mostly tothe class lnsecta, comprising six-legged, usually winged forms, asbeetles, bugs, bees, flies, and so forth, but also to other alliedclasses of arthropods whose members are Wingless and usually have morethan six legs, as spiders, mites, ticks, centipedes, millipedes, andwood lice.

The activity of these compounds against the corn 'rootworm isillustrated by the following:

To a growth pouch (diSPo Seed-Pak growth pouch, Catalogue No. B1220, ofScientific Products Division of American Hospital Supply Corporation,Evanston, Illinois) in an upright position is added 20 ml. of distilledwater. Thereafter is added 0.1 ml. of an acetone solution of knownconcentration in percent by weight of a compound of this invention (forexample an 0.1 ml. of an 0.1 percent by weight acetone solution of thecompound provides a concentration of 5.0 ppm. thereof while 0.1 ml. ofan 0.02 percent by weight acetone solution of the said compound provides'a concentration of 1.0 ppm thereof). In the trough of the pouch formedby the paper wick thereof is placed two corn seeds (Zea mays, HybridU.S. 13) about one inch apart. Thereupon to the trough and between theseeds is added 8 to 12 ready-to-hatch eggs of the southern corn rootworm(Diabrotica undecimpunctata howardi), which eggs were washed (withdistilled water) free of the soil in which they were incubated at roomtemperature for 21 days immediately prior to their placement in thetrough. The socharged growth pouch is then placed in an upright positionin an incubator maintained at 80F and 70 percent relative humidity for14 days. immediately thereafter the growth pouches are removed and theextent of kill in percent of the particular species of corn rootwormlarvae observed. At a concentration of 5 ppm., a 100 percent kill wasobserved with m-isopropylphenyl-N-isobutenyl-N- methylcarbamate and alsowith m-isopropylphenyl-N- (2-ethyl-1-buteny1)-N-rnethylcarbamate. Whenused at the same concentration, a mixture of m-(lmethylbutyl)phenyl-N-isobutenyl-N-methylcarbamate and m-(l-ethylpropyl)phenyl-N-isobutenyl-N- methylcarbamate gave a 60 percentkill.

To demonstrate the activity of the compounds of this invention againstthe western corn rootworm (Diabrotica virgzfera), compounds wereincorporated into separate portions of soil containing sections of cornroots. Each portion of the soil was then infested with 10-day oldwestern corn root larvae and maintained at 25C and 70 percent relativehumidity for 48 hours. At concentrations of 6 ppm., 100 percent killswere obtained with (l m-tolyl-N-( l-cyclohexen-l-yl)- N-methylcarbamate,(2) m-isopropylphenyl-N-(Z- ethyl-l-buten-l-yl)-N-methylcarbamate, (3)m-tolyl- N-(1-cyclohexen-l-yl)-N-methylcarbamate, and (4) a mixture ofin-( l-methylbutyl) phenyl-N-( l-isobuten-lyl)-N-methylcarbamate and m-(l-ethylpropyl) phenyl- N-( l-isobutenl -yl)-N-methylcarbamate.

The compounds of the present invention are also quite effective againstthe boll weevil (Anlhonomus grandis) and the bollworm (Heliothis zea).For example, when cotton fields are sprayed at the rate of 10 pounds peracre with m-tolyl-N-( l-cyclohexen-l -yl )-N- methylcarbamate, a 60percent kill of the boll weevil is obtained. The same compound, whenapplied to leaves of cotton plants at a concentration of only 0.05percent, resulted in a 60 percent kill of the bollworm.

The present compounds are also effective against the yellow fevermosquito (Aedes egypn'). For example, 100

v percent kills were obtained in a standard life cycle test with 2 ppm.of a mixture of m-( l-methylbutyl)phenyl- N-(l-isobuten-l-yl)-N-methylcarbamate and m-( lmethylcarbamate, 2 ppm. of amixture of m-( 2- ethylpropyl)phenyl-N-( 2-ethyll -hexenl -yl)-N-methylcarbamate and m-(l-methylbutyl)phenyl-N-(2ethyl-l-hexen-l-yl)-N-methylcarbamate and 0.2 ppm. ofm-isopropy1phenyl-N-( Z-ethyl- 1 -buten- 1 -yl)-N- methylcarbamate.

Although the compounds of this invention are useful per se incontrolling a wide variety of insect pests, it is preferable that theybe supplied to the pests or to the environment of the pests in adispersed form in a suitable extending agent.

The term dispersed is used herein in its widest possible sense. When itis said that the compounds of this invention are dispersed, it meansthat particles of the compounds may be molecular in size and held intrue solution in a suitable organic solvent. it means further, that theparticles may be colloidal in size and distributed throughout a liquidphase in the form of suspensions or emulsions or in the form ofparticles held in suspension by wetting agents. It also includesparticles which are distributed in a semi-solid viscous carrier such aspetrolatum or soap or other ointment base in which they may be actuallydissolved in the semi-solid or held in suspension in the semi-solid withthe aid of suitable wetting or emulsifying agents. The term dispersed"also means that the particles may be mixed with and distributedthroughout a solid carrier providing a mixture in particulate form,e.g., pellets, granules, powders, or dusts. The term dispersed alsoincludes mixtures which are suitable for use as aerosols includingsolutions, suspensions, or emulsions of the compounds of this inventionin a carrier such as dichlorodifluorornethane and the likefluorochloroalkanes which boil below room temperature at atmosphericpressure.

The expression extending agent as used herein includes insecticidaladjuvants and any and all of the substances in which the compounds ofthis invention are dispersed. It includes, therefore, the solvents of atrue solution, the liquid phase of suspensions, emulsions or aerosols,the semi-solid carrier of ointments and the solid phase of particulatesolids, e.g., pellets, granules, dusts and powders.

The exact concentration of the compounds of this invention employed incombatting or controlling insect pests can vary considerably providedthe required dosage (i.e., toxic or lethal amount) thereof is suppliedto the pests or to the environment of the pests. When the extendingagent is a liquid or mixture of liquids (e.g., as in solutions,suspensions, emulsions, or aerosols) the concentration of the activecompound employed to supply the desired dosage generally will be in therange of 0.0001 to 50 percent by weight. When the extending agent is asemi-solid or solid, the concentration of the compound employed tosupply the desired dosage generally will be in the range of 0.1 to 80percent by weight. From a practical point of view, the manufacturer mustsupply the user with a concentrate in such form that, by merely mixingwith water of solid extender (e.g., powdered clay or talc) or otherlow-cost material available to the user at the point of use, he willhave an easily prepared insecticidal spray or particulate solid. In sucha concentrate composition, the compound generally will be present in aconcentration of 5 to 95 percent by weight, the residue being any one ormore of the well-known insecticidal adjuvants, such as the-varioussurface active agents (e.g., detergents, a soap or other emulsifying orwetting agent), surfaceactive clays, solvents, diluents, carrier media,adhesives, spreading agents, humectants, and the like.

The compounds of this invention are preferably supplied to the insectpests or to the environment of the insect pests in the form ofemulsionsor suspensions. Emulsions or suspensions are prepared bydispersing the compounds either per se or in the form of an organicsolution thereof in water with the aid of a watersoluble surfactant. Theterm surfactant as employed herein is used as in volume II of Schwartz,Perry and Berch's Surface Active Agents and Detergents (i958,lnterscience Publishers Inc., New York) in place of the expression"emulsifying agent" to connote generically the various emulsifyingagents," dispersing agents," wetting agents and spreading agents" thatare adapted to be admixed with the active compounds of this invention inorder to secure better wetdescribed in detail in volumes I and II ofSchwartz,

Perry and Berchs Surface Active Agents and Detergents (1958,Interscience Publishers, Inc., N.Y.) and also in the November, 1947issue of Chemical Industries (pages 811-824) in an article entitledSynthetic Detergents" by John W. McCutcheon and also in the July,August, September, and October 1952 issues of Soap and SanitaryChemicals under the title Synthetic Detergents." The disclosures ofthese articles with respect to surfactants are incorporated in thisspecification by reference in order to avoid unnecessary enlargement ofthis specification. The preferred surfactants are the water-solubleanionic non-ionic surfaceactive agents set forth in US. Pat. No.2,846,398 (issued Aug. 5, 1958). In general, a mixture of watersolubleanionic and water-soluble non-ionic surfactants is preferred.

The compounds of this invention can be dispersed by suitable methods(e.g., tumbling or grinding) in solid extending agents either of organicor inorganic nature and supplied to the insect pests environment inparticulate form. Such solid materials include for example, tricalciumphosphate, calcium carbonate, kaolin, bole, kieselguhr, talc, bentonite,fullers earth, pyrophillite, diatomaceous earth, calcined magnesia,volcanic ash, sulfur and the like inorganic solid materials as well asorganic materials such as powdered cork, powdered wood, and powderedwalnut shells. The preferred solid carriers are the adsorbent clays,e.g., bentonite. These mixtures can be used for insecticidal purposes inthe dry form, or by addition of watersoluble surfactants or wettingagents, the dry particulate solids can be rendered wettable by water soas to obtain stable aqueous dispersions or suspensions suitable for useas sprays.

For special purpose the compounds of this invention can be dispersed ina semisolid extending agent such as petroleum or soap (e.g., sodiumstearate or oleate or palmitate or mixtures thereof) with or without theaid of solubility promoters and/or surfactants or dispersing agents.

In all of the forms described above the dispersions can be providedready for use in combatting insect pests or they can be provided in aconcentrated form suitable for mixing with or dispersing in otherextending agents. As illustrative of a particularly useful concentrateis an intimate mixtureof a compound of this invention with awater-soluble surfactant in the weight proportions of 0.1 to 15 parts ofsurfactant with sufficient phosphonate to make parts by weight. Such aconcentrate is particularly adapted to be made into a spray forcombatting various forms of insect pests by the addition of waterthereto.

Another useful concentrate adapted to be made into a spray forcombatting a variety of insect pests is a solution (preferably asconcentrated as possible) of a compound of this invention in an organicsolvent therefor. The said liquid concentrate preferably containsdissolved therein a minor amount (e.g., 0.5 to 10 percent by weight ofthe weight of the new insecticidal agent) of a water-soluble surfactant(or emulsifying agent).

Emulsifiable concentrates of this general type are particularly welladapted for use as sheep and cattle dips in the control of animalparasites. In preparing such dips, a compound of this invention isdissolved in a water-immiscible solvent system and a sufficient quantityof one or more emulsifying agents is added to insure the formation of astable aqueous emulsion. Water is then added to the concentrate to forman emulsion containing from about 0.01 percent to about 0.5 percent ofthe active ingredient.

Of the surfactants aforementioned in preparing the various emulsifiable,wettable or dispersible compositions or concentrates of this invention,the anionic and non-ionic surfactants are preferred. Of the anionicsurfactants, the particularly preferred are the well known ylenederivatives of the mono-higher fatty acid esters of hexitol anhydrides(e.g. sorbitan). These materials in general contain to moles of ethyleneoxide per mole of the hexitol anhydride or the alkylphenol.

The compositions of this invention can also contain other additimentssuch as fertilizers and pesticides used as, or in combination with, thecarrier materials. For example, the pesticides listed in US. Pat. No.3,393,990 starting at line 68, column 7 and extending through line 7l ofcolumn 8, can be used in combination with the above described compounds.

in controlling or combatting insect pests the compounds of thisinvention either per se or compositions containing them are supplied tothe insect pests or to their environment in a lethal or toxic amount.This can be done by dispersing the new insecticidal agent orinsecticidal composition comprising same in, on or over an infestedenvironment or in, on or over an environment the insect pests frequent,e.g., agricultural soil or other growth media or other media infestedwith insect pests or attractable to the pests for habitational orsustenance or propagational purposes, in any conventional fashion whichpermits contact between the insect pests and the compounds of thisinvention. Such dispersing can be brought about by applying sprays, dipsor particulate solid compositions to a surface infested with the insectpests or attractable to the pests as for example, animals such as sheepand cattle, the surface of an agricultural soil or other media such asthe above ground surface of plants by any of the conventional methods,e.g., power dusters, boom and hand sprayers, and spray dusters. Also forsub-surface application such dispersing can be carried out by simplymixing the new insectisolid compositions comprising same with theinfested environment or with the environment the insect pests frequent,or by employing a liquid carrier for the new insecticidal agent toaccomplish subsurface penetration and impregnation therein.

While this invention has been described with respect to certainembodiments, it is to be understood that it is not so limited and thatvariations and modifications thereof obvious to those skilled in the artcan be made without departing from the spirit and scope thereof.

l claim:

1. A method of combatting insects which comprises contacting saidinsects with a toxic amount of misopropylphenyl-N-( l-isobuten- 1-yl)-N-methylcarbamate.

2. A method of combatting insects which comprises contacting saidinsects with a toxic amount of mmethylphenyl-N-( l-cyclohexenl -yl )-N-methylcarbamate.

3. A method of combatting insects which comprises contacting saidinsects with a toxic amount of mpentylphenyl-N-( l -isobuten- 1-yl)-N-methylcarbamate.

4. A method of combatting insects which comprises contacting saidinsects with a toxic amount of misopropylphenyl-N-( l-iso'pentenl-yl)-N- methylcarbamate.

5. A method of combatting insects which comprises contacting saidinsects with a toxic amount of mpentylphenyl-N-( 2-ethyl-l -hexenl-yl)-N- methylcarbamate.

6. An insecticidal composition comprising an insecticidal adjuvant, andas an active ingredient, a toxic amount ofm-isopropylphenyl-N-(l-isobuten-l-yl)-N- methylcarbamate.

2. A method of combatting insects which comprises contacting saidinsects with a toxic amount ofm-methylphenyl-N-(1-cyclohexen-1-yl)-N-methylcarbamate.
 3. A method ofcombatting insects which comprises contacting said insects with a toxicamount of m-pentylphenyl-N-(1-isobuten-1-yl)-N-methylcarbamate.
 4. Amethod of combatting insects which comprises contacting said insectswith a toxic amount ofm-isopropylphenyl-N-(1-isopenten-1-yl)-N-methylcarbamate.
 5. A method ofcombatting insects which comprises contacting said insects with a toxicamount of m-pentylphenyl-N-(2-ethyl-1-hexen-1-yl)-N-methylcarbamate. 6.An insecticidal composition comprising an insecticidal adjuvant, and asan active ingredient, a toxic amount ofm-isopropylphenyl-N-(1-isobuten-1-yl)-N-methylcarbamate.
 7. Aninsecticidal composition comprising an insecticidal adjuvant, and as anactive ingredient, a toxic amount ofm-methylphenyl-N-(1-cyclohexen-1-yl)-N-methylcarbamate.
 8. Aninsecticidal composition comprising an insecticidal adjuvant, and as anactive ingredient, a toxic amount ofm-pentylphenyl-N-(1-isobuten-1-yl)-N-methylcarbamate.
 9. An insecticidalcomposition comprising an insecticidal adjuvant, and as an activeingredient, a toxic amount ofm-isopropylphenyl-N-(1-isopenten-1-yl)-N-methylcarbamate.
 10. Aninsecticidal composition comprising an insecticidal adjuvant, and as anactive ingredient, a toxic amount ofm-pentylphenyl-N-(2-ethyl-1-hexen-1-yl)-N-methylcarbamate.